A lead mechanic and line mechanic report about a number 2 engine anti-ice valve that was not locked-...

Narrative:

Aircraft X is the aircraft involved in event. Mechanic Y and Z were the mechanics assigned to the aircraft that night. I was the lead mechanic assisting with the troubleshooting. This event occurred at night; december 2013 and into the following morning. The aircraft was parked in the remote parking location adjacent to gate 38. Aircraft X had an MEL on the number 2 engine anti-ice valve which was to be locked 'open' for revenue service. During troubleshooting of problem; valve was unlocked and allowed to close to the normally 'closed' position. We performed the troubleshooting without issue. The troubleshooting consisted of an operational check of the valve and wiring checks. After troubleshooting had ended; mechanics Y and Z were instructed to lock valve 'open' and close fan cowls in preparation for service. The aircraft flew revenue service for four legs when the problem was discovered. The anti-ice valve was not locked 'open' as prescribed per the MEL. After landing in ZZZ1; the pilot wrote in the logbook his observations of the aircraft's performance and questioned it in comparison to the MEL procedure. Maintenance personnel in ZZZ1 looked into the issue as the aircraft was scheduled for maintenance that night at ZZZ1. It was at this time that ZZZ1 maintenance discovered the valve not locked 'open' per MEL requirement. I believe that a lack of experience and knowledge on behalf of mechanics Y and Z played a role in the incident. Another cause was my trust in mechanics Y and Z to accomplish the work properly. I did not check the work of less experienced mechanics to ensure the MEL was properly restored. To my knowledge; ZZZ1 maintenance locked the anti-ice valve in the 'open' position to comply with MEL procedure and signed-off the logbook write-up concerning the anti-ice valve. Would [recommend] to [do] better to oversee maintenance as a lead mechanic to ensure proper maintenance is performed. Also; make sure the mechanics understand better what procedures must take place when working with mels.

Original NASA ASRS Text

Title: A Lead Mechanic and Line Mechanic report about a Number 2 Engine Anti-Ice Valve that was not locked-out in the 'Open' position as required for an MEL deferral on an Airbus aircraft.

Narrative: Aircraft X is the aircraft involved in event. Mechanic Y and Z were the Mechanics assigned to the aircraft that night. I was the Lead Mechanic assisting with the troubleshooting. This event occurred at night; December 2013 and into the following morning. The aircraft was parked in the remote parking location adjacent to Gate 38. Aircraft X had an MEL on the Number 2 Engine Anti-Ice Valve which was to be locked 'Open' for revenue service. During troubleshooting of problem; Valve was unlocked and allowed to close to the normally 'Closed' position. We performed the troubleshooting without issue. The troubleshooting consisted of an operational check of the valve and wiring checks. After Troubleshooting had ended; Mechanics Y and Z were instructed to lock valve 'Open' and close Fan cowls in preparation for service. The aircraft flew revenue service for four legs when the problem was discovered. The Anti-Ice valve was not locked 'Open' as prescribed per the MEL. After landing in ZZZ1; the pilot wrote in the Logbook his observations of the aircraft's performance and questioned it in comparison to the MEL procedure. Maintenance personnel in ZZZ1 looked into the issue as the aircraft was scheduled for Maintenance that night at ZZZ1. It was at this time that ZZZ1 Maintenance discovered the valve not locked 'Open' per MEL requirement. I believe that a lack of experience and knowledge on behalf of Mechanics Y and Z played a role in the incident. Another cause was my trust in Mechanics Y and Z to accomplish the work properly. I did not check the work of less experienced mechanics to ensure the MEL was properly restored. To my knowledge; ZZZ1 Maintenance locked the Anti-Ice Valve in the 'open' position to comply with MEL procedure and signed-off the Logbook write-up concerning the Anti-Ice valve. Would [recommend] to [do] better to oversee Maintenance as a Lead Mechanic to ensure proper maintenance is performed. Also; make sure the mechanics understand better what procedures must take place when working with MELs.

Data retrieved from NASA's ASRS site as of July 2013 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.

Attributes
ACN	1059301
Time
Date	201212
Local Time Of Day	0001-0600
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Light	Night
Aircraft 1
Make Model Name	A321
Operating Under FAR Part	Part 121
Flight Phase	Parked
Component
Aircraft Component	Engine Air Anti-Ice
Person 1
Function	Lead Technician
Qualification	Maintenance Powerplant Maintenance Airframe
Person 2
Function	Technician
Qualification	Maintenance Powerplant Maintenance Airframe
Events
Anomaly	Aircraft Equipment Problem Critical Deviation - Procedural MEL Deviation - Procedural Published Material / Policy

A lead mechanic and line mechanic report about a number 2 engine anti-ice valve that was not locked-out in the 'open' position as required for an MEL deferral on an airbus aircraft.